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Acta of Bioengineering and Biomechanics

Tytuł artykułu

Evaluating the material parameters of the human cornea in a numerical model

Autorzy Śródka, W. 
Treść / Zawartość
Warianty tytułu
Języki publikacji EN
EN The values of the biomechanical human eyeball model parameters reported in the literature are still being disputed. The primary motivation behind this work was to predict the material parameters of the cornea through numerical simulations and to assess the applicability of the ubiquitously accepted law of applanation tonometry – the Imbert–Fick equation. Methods: Numerical simulations of a few states of eyeball loading were run to determine the stroma material parameters. In the computations, the elasticity moduli of the material were related to the stress sign, instead of the orientation in space. Results: Stroma elasticity secant modulus E was predicted to be close to 0.3 MPa. The numerically simulated applanation tonometer readings for the cornea with the calibration dimensions were found to be lower by 11 mmHg then IOP = 48 mmHg. Conclusions: This discrepancy is the result of a strictly mechanical phenomenon taking place in the tensioned and simultaneously flattened corneal shell and is not related to the tonometer measuring accuracy. The observed deviation has not been amenable to any GAT corrections, contradicting the Imbert–Fick law. This means a new approach to the calculation of corrections for GAT readings is needed.
Słowa kluczowe
PL oko   tonometria   IOP   model biomechaniczny  
EN eyeball   biomechanical model   tonometry   IOP  
Wydawca Oficyna Wydawnicza Politechniki Wrocławskiej
Czasopismo Acta of Bioengineering and Biomechanics
Rocznik 2011
Tom Vol. 13, nr 3
Strony 77--85
Opis fizyczny Bibliogr. 36 poz., il.
autor Śródka, W.
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